In general, a fuel cell is a device that obtains electrical power from fuel, hydrogen and oxygen. Fuel cells are being widely developed as an energy supply device because fuel cells are environmentally superior and can achieve high energy efficiency.
The fuel cell has a structure in which a plurality of electrical power generators is stacked with a separator being interposed therebetween, the electrical power generator having a structure in which an anode and a cathode hold an electrolyte therebetween. A recess is formed on the separator and is used as a passageway of reactant gas provided from outside. With the structure, the reactant gas provided to the separator from outside is provided to the anode and the cathode, and the fuel cell generates electrical power.
Patent Document 1 discloses a fuel cell having a separator and a strengthening-substrate that strengthens the electrolyte. With the fuel cell, a contact resistance is reduced because members are electrically conducted. An electric generation efficiency of the fuel cell is therefore increased.    Patent Document 1: Japanese Patent Application Publication No. 3-110761